Cabin Heater Info

25 posts in this topic

Posted

Hello all, I'm putting heat in the plane this winter. ( A little late I know) but it's for next year. Does anyone know the size of the heater core required or the fan sizes I should look for? Any other parts necessary? Lot's of confusing info out there and I'd like to get something that works on the first try.

Thanks, Terry

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Posted

Lots of variables.  What kind of plane, what engine, ect, ect.....JImChuk

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Posted

UPI also sells three speed switch but they are NOT COMPATIBLE with the fan, use a good toggle switch.  To build the air box fiber glass works great. Cut a piece of foam insulation (1 1/2”) thick to fit the top, duct tape over it tapei the sides of the heater core and then fiberglass over it. I use epoxy resin but polyester will work ok.  Bidirectional cloth works best. Once the air box is complete remove the foam and tape, cut the fan opening and bolt the fan to the box.  A diode across the leads of the fan was necessary with my installation due to a large back emf spike when the fan starts.

Mounted mine under the panel with an aluminum deflector to direct the heat off my shins.  Sorry I don’t have any pictures of the build or installation.  I tried some computer fan but not enough air flow.  The above fan has plenty of flow.  No valve is necessary on th water lines.

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Posted

I have a late model C with most of the model IV mods, Just finished it up this summer.

 

 

PXL_20220422_154622734.jpg

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Posted

Oops...Rotax 582 Blue Head.

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Posted

Damn! That is a beautiful plane!

For virtually NO weight addition compared to adding a radiator, fan etc., you can build the original Avid heat system that captures air off the back of the passenger radiator, and direct it into the cabin with flexible hose. It provides some heat, and it also allows the engine to warm better in the winter. You just remove it in the summer. I would do that even if I went to the trouble to add a heat radiator and fan, because when it is really cold out there you are going to want every bit of heat you can get!

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Posted

I built a muffler shroud for my 582 muffler and it worked pretty good.  I ended up fitting a fiberglass "funnel" behind the radiator like Chris talked about in his last post to push air though the muffler shroud.  That did produce pretty good heat.  Had to put the muffler mounts on the ends of the muffler and hang it off the firewall, but that is a better way to hang the muffler anyway.  The tubing Avid used that hangs from the engine is subject to cracking.  Heater thoughts? - Technical tasks - AvidFoxFlyers Forums  have a look at this thread to see what I did.  This was before I connected inlet air to the back of the radiator.  That improved the heat considerably.  JImChuk

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Posted

Thanks to all for the excellent advice, I'm north of Toronto, Canada and it gets pretty cold here in the winter. From what research I have done so far it seems that the water type heater gives a better heat than the muffler shroud, and most of the Kitfox types have gone to water heat I think they use it in Challengers too. I'm not against the muffler shroud but would just like to put in the best system for maximum heat output. I know I'll need it all at some point during the winter. I really like your heat muff system Jim and if I go that way you have provided great pictures and info for me to follow.

Thanks, Terry

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Posted

I'm in northern Mn, so we see plenty of cold weather as well.  In fact, it's +16 F and we have 6" of snow on the ground right now.  The thing with coolant for heat, is when you want it the most, the engine will be cooled as well and have a harder time giving some to you.  The muffler will get hot anytime you are running at cruise rpm.   I do have a heater core running on my Kitfox 4, and it does ok.  JImChuk

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Posted (edited)

I think the best option might be (although I haven't tried it) one of these miniature diesel turbine heaters. 

https://www.vevor.com/diesel-heater-c_10321/diesel-air-heater-5kw-12v-lcd-display-all-in-one-for-truck-rvs-car-motorhomes-p_010633661202?utm_source=google&utm_campaign=14208751102&utm_term=126423776860&gclid=Cj0KCQiA99ybBhD9ARIsALvZavVfpa8zCphC1LMTxySKGZjcWODZxtNLEaKS8IFfIEvBx8MEhU2wAb0aAieXEALw_wcB

or 

https://www.vevor.com/diesel-heater-c_10321/2kw-12v-diesel-air-heater-lcd-switch-2000w-for-trucks-boats-car-bus-trailer-p_010198386270?utm_source=google&utm_campaign=14398577900&utm_term=128016354204&gclid=Cj0KCQiA99ybBhD9ARIsALvZavV_U069zcjgJfckGVslra540PrVXPYVAYSurRjyPvsL2qmsTNFOGgYaAoGuEALw_wcB

You get the idea. There are lots of them out there. Depending on the model they are very small, cheap, lightweight and produce a TON of good clean heat. I think they come typically with a couple gallon fuel container, but a half pint would work for hours.

The only thing required is a small hole for the exhaust to exit to the outside the cabin.

Edited by ChrisBolkan

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Posted

Hi Chris...they sure look interesting, I just wonder if there would be a significant fire hazard with them, and where they could be safely mounted in a fabric plane?

Jim knowing what you know having had both systems....would you choose one type over the other? I lean towards the heat muff only because I am more familiar with it.

Thanks, Terry

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Posted

Each one had good and bad points.  The heat muff I had on the 582 worked good for it.  With the 912 in the Kitfox, I have a thermostat (thermo-bob) and you run a bypass line off of it and go through the heater core with that bypass line.  When the thermostat opens, the coolant wants to flow through that larger hose, and you loose some heat.  When I do the next one, I will run the 1" line through the heater core (I have one with 1" fittings) and the thermostat will be down stream of the heater core.  That should do real well for heat then.  Trouble with the heater core, is everything gets so cramped for space.  Like 10 lbs of crap in a 5 lb bag.....  JImChuk

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Posted

Thanks for all the very great info everyone, I've decided to go with the radiator core water heater version for heat. Can anyone supply the model number or dimensions of the Kitfox cooler and fittings, and perhaps installation instructions?

Thanks , Terry

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Posted

Be well aware of cold seizure issues - you don't want coolant returning to the engine too cool!

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Posted (edited)

The factory heater works reasonably well on my Avid Mk IV, and was easy to install. I would bet the diesel heater is much more effective, and the water  radiator heater is probably just the same as this factory one (same radiator area?).

Here is my installation, note the flapper valve box on the firewall is actuated by a pull cable I installed, using a cheap choke cable kit.

IMG_1358.jpg

 

image1.jpeg

Edited by nlappos

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Posted

Thanks for the pics, the will help for sure, Terry

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Posted

My MKIV had the heater pick off on the other radiator. The hose came right by the air cleaners and straight into the cockpit. That allowed it to avoid being routed by the exhaust, which could be bad with exhaust possibly damaging the tubing and a more complex routing, but probably good it terms of minimal heat loss.

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Posted

With the double radiators, one will have hotter coolant than the other.  Therefore you would want to use the first one in the run.  As I remember, that is the one on the right (passenger)side.  Memory isn't always the best though.... JImChuk

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Posted

Thanks Jim changed my mind and starting to make the cabin heat box....maybe one on each side? and what size 2 or 3 inch scat tube?

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Posted

I have an unused Avid heat box and a fiberglass radiator scoop.  JImChuk

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Posted

Hi Jim, I sent you a message, at least I think I did :)

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Posted

got it and replied

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Posted

The factory heater works reasonably well on my Avid Mk IV, and was easy to install. I would bet the diesel heater is much more effective, and the water  radiator heater is probably just the same as this factory one (same radiator area?).

Here is my installation, note the flapper valve box on the firewall is actuated by a pull cable I installed, using a cheap choke cable kit.

How cold does it get around you?

 

 

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Posted

Don't see any pics TJay.... we get to about -20F but it's a dry cold. We always get a nice January thaw for a few days as well.  I wouldn' feel comfortable with the diesel heaters, the fire risk would worry me althogh I could see using one as an engine pre- heater as they do produce a lot of heat.

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